1. Field of the Invention
The present invention relates to an image forming apparatus, an image forming method, and a storage medium.
2. Description of the Related Art
In the printing industry, color toners of cyan (C), magenta (M), yellow (Y), and black (K), which are called “process color,” are commonly used. However, a specific color such as a corporate color used in a particular corporation may not be expressed with process color when it is desired to ensure its beautiful expression. Therefore, a so-called specific color toner produced by original blending is commonly used. In printers capable of using a specific color toner, part of an image of a specific color is printed using the specific color toner, while the other part of the image is printed using process color toners.
However, in order to perform printing that precisely expresses a specific color in a general-purpose image forming apparatus, it is necessary to define the specific color in the apparatus body or on an application for printing (a printing application). The specific color is a color of an original blend based on a customer's request. Therefore, in the case of forming an image of the specific color using four color toners of C, M, Y, and K, it is necessary to measure color components with a colorimeter and register the measured color components with the image forming apparatus in order to express the specific color as precisely as possible.
Japanese Patent Application No. 2006-155499 discloses a technique related to an image forming system that includes a specific color registration determination part configured to determine whether to register a specific color in a host computer, an image data generation part configured to generate image data in the host computer, a specific color data detection part configured to retrieve specific color data from the image data generated by the image data generation part, an image forming part configured to form an image from the image data, and a specific color registration part configured to register the specific color data detected by the specific color detection part with the image forming part.
Japanese Laid-Open Patent Application No. 2005-229475 discloses a technique related to a data converter that includes a storage part configured to store a specific color and a corresponding combination of the amounts of process colors in correlation with each other, a combination candidate generation part configured to generate multiple combination candidates including the combination, a patch image creating part configured to cause an output device to output multiple color patches corresponding to the respective combination candidates, a color patch specifying part configured to receive a specified one of the color patches, a combination updating part configured to replace the combination of the amounts of process colors stored in the storage part with the combination candidate of the specified color patch, an image data obtaining part configured to obtain first image data representing an image including the specific color, and an image data conversion part configured to convert the first image data into second image data where the specific color is reproduced with the corresponding combination of the amounts of process colors correlated with the specific color.
Thus, conventionally, image forming apparatuses are common that express a specific color using four color toners of C, M, Y, and K, while in recent years, image forming apparatuses capable of performing printing using a fifth and a sixth color toner have been widely used. Therefore, techniques have been proposed that print specific colors using specific color toners as a fifth and a sixth color toner.
Japanese Laid-Open Patent Application No. 2008-170474 discloses an image forming apparatus capable of using an extension function using specific toner, where it is determined whether the image forming apparatus is loaded with the specific toner, an image forming function is extended based on the determination result, and an image is formed using the specific toner with the extended function.